1. Field of the Invention
This invention relates to the field of recording on photosensitive direct print recording media or paper, and more specifically, to apparatus for latensifying images which have been recorded on such media thereby to provide rapid access to the recorded information.
2. Description of the Prior Art
Recording media or paper which have on one surface an emulsion which is sensitive to invisible radiations, for example, radiations in the ultraviolet region, are known. The emulsions of such photographic papers may have a variety of compositions, the basic constituents usually consisting, however, of a silver halide compound in a matrix of gelatin. Typical of such commercially available papers are the direct print papers sold by Eastman Kodak Company under the trade designations "Kodak 2167" and "Kodak LDP".
It is also known in the prior art to render visible images recorded on the emulsion of such photographic papers by chemical treatment or exposure to radiation of low energy or intensity. Such intensification of the latent image is referred to as latensification. Thus, it has been proposed in the prior art to effect latensification of direct print recording media by first subjecting the emulsion having the latent image to heat and thereafter exposing the emulsion for an interval to radiations within the band of wavelengths to which the emulsion primarily is sensitive. Such a latensifying arrangement is illustrated in U.S. Pat. No. 3,143,940 of R. P. Brown et al, issued Aug. 11, 1964. In another prior art arrangement, as illustrated in U.S. Pat. No. 3,229,299, R. D. Erickson dated Jan. 11, 1966, heat is not employed. The latensification there is effected by successively exposing the emulsion having the latent image first for a short time to a low intensity state of radiation having wavelengths to which the emulsion is primarily responsive, and thereafter, to a high intensity latensifying radiation having the same wavelengths.
Producing a visible record on direct print or photodeveloped recording media thus requires a period of exposure to radiation of substantially the same wavelengths as those to which the emulsion is primarily sensitive. Where the recording speed is substantially constant, such latensification is effective to provide rapid access to the recorded information. For those recording applications where the recording speed is variable, however, the period of exposure required for latensification results in significant disadvantage particularly when rapid access to or an immediate view of the recorded data is desired.